The Truth About Cars » ATF The Truth About Cars is dedicated to providing candid, unbiased automobile reviews and the latest in auto industry news. Thu, 17 Jul 2014 20:36:40 +0000 en-US hourly 1 The Truth About Cars is dedicated to providing candid, unbiased automobile reviews and the latest in auto industry news. The Truth About Cars no The Truth About Cars (The Truth About Cars) 2006-2009 The Truth About Cars The Truth About Cars is dedicated to providing candid, unbiased automobile reviews and the latest in auto industry news. The Truth About Cars » ATF Piston Slap: Crystal Ballin’ With Yo Tranny! (Part II) Wed, 09 Apr 2014 12:24:30 +0000 Anything is Possible... (photo courtesy:

Aaron writes:

Hey Sajeev,

Huge fan of TTAC and the piston slap articles. My problem is that I noticed my car(2007 honda civic)would shudder, under light throttle and low rpms especially when going up a slight slope. This usually happens at 30km/hr or 40km/hr. I took it to the honda dealer(4 months ago) and he said the torque converter(tc) needs to be replaced(300 for tc plus 900 for labour and stuff).

My university got a bit busy and I took some time to think about it. The problem might be slightly worse now so I recently went back to the dealer to get more details about the cost and now they are saying the price of the tc has increased to 800 plus another 800 for labour. The guy suggested maybe just changing the transmission fluid(because it is starting to get dark) and driving the car until it fails and getting a new transmission for $3000 because the transmission will probably go out soon anyway.

I’m not sure what to do now. I’m considering going to a transmission shop and see if they can change the tc, but I’m worried about going to a random mechanic. I know a small time mechanic whom I go to for small stuff but I’m not sure if his shop is capable of swapping the tc(is it that complicated?). I have also looked online and found other people saying that if the torque converter is failing, the transmission is probably going to go soon. Some other people have said that if the torque converter fails, it could take out the rest of the transmission which might have been working fine otherwise. I then found another group of people saying that I should just drive the car without changing the transmission fluid because even changing the fluid could cause the transmission to fail sooner.

I just want to know which of these are actually true and what should my next course of action be. If the torque converter can be changed for a reasonable price and my transmission keeps working, I would like to do that. Or maybe I should see if I can get the entire transmission rebuilt or replaced.

Thank you,

P.S: Not sure if this matters, but the car once overheated severely (about 3 years ago) and about half the engine had to be replaced under warranty. The engine has been running smoothly since then and the only other problem is that recently(2 months ago) my engine starter and battery had to be replaced. The battery connectors also look pretty bad so I’m going to replace that soon. Hmmm maybe I should just sell my car.

Sajeev answers:

Oh great, another mystery box transaxle/crystal ballin’ yo tranny problem: one day the B&B will string me up for these blind guesses.

That said, on a more serious note, how many miles are on the Civic?

Aaron responds:

Hey Sajeev,

Thanks for the quick reply. It has 156,000 km(96,000 miles). Admittedly, the car has been driven pretty hard. I just did a quick stall speed test(mashing the brake and hitting the throttle) and the revs went up to 2,500rpm in both drive and reverse. That seems pretty normal. I drove around trying to recreate the problem(Light throttle and flat roads or slight inclines).

It happens at:

  • 15 or 20km/h (9 or 12mph)
  • 30ish km/h (18mph)
  • 40ish km/h (25mph)
  • And at 55ish km/h (34.18mph), the shuddering is only minor at this speed

There is also a sound when this happens, it sounds like metal spinning against metal in a liquid. However, this sound can only be heard if the shuddering is not too violent. If it is violent, it just sounds like the car kind of wants to stall. I checked the transmission fluid and it looks pretty brown and has a slight burning smell. If the car is accelerating faster( atleast above 2000rpm), it feels like there is no problem. Also no problem when slowing down.
Thank you,

Sajeev concludes:

Great assessment!  At this age (under 100k miles) odds are new and correct fluid will solve it: flush the old fluid out of the converter and also drop the pan to change the filter. Which might be asking a lot for many shops, but I’d want all the old ATF out of the system. So will this cure the problem?  Will thoroughly removing varnished ATF cause even more problems than a shudder?

Maybe on both counts.  Or maybe one and not the other.  See how much fun this is for me?

My best guess: do as the dealer said, change the fluid. If it fails, get a rebuilt transaxle from a Honda savvy shop.  Because opening up a transaxle for anything and not doing a rebuild is likely a waste of time, labor and money.

It’s usually best to prolong that moment with anything…including a fluid change. Even if the fluid change actually shortens the tranny’s lifespan. So much fun!

Send your queries to Spare no details and ask for a speedy resolution if you’re in a hurry…but be realistic, and use your make/model specific forums instead of TTAC for more timely advice.

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Piston Slap: Sealed for an Infinite Life? Mon, 14 Oct 2013 12:11:58 +0000 Jerry writes:


Thank you and the rest of the TTAC staff for providing the community with an entertaining and genuinely informative automotive website. I’m a long-time reader, and hope you can answer some questions I had about my wife’s 2009 G37 S 7AT.

We purchased the car new in 2009 and love it. It’s paid off and we see no reason to replace it anytime in the foreseeable future. It’s a keeper.

We carpool and thus only have accumulated 29,xxx miles in the years we’ve owned it. I try to be diligent with my vehicle servicing, and prefer to do my own maintenance. When preparing for the upcoming 30,000 mile service, I noticed something peculiar in the maintenance schedule provided by Infiniti:

‘Replace automatic transmission fluid(except 7 speed automatic transmission).’

Even more curious, the 7 speed automatic is not recommended for servicing at any point in the published maintenance schedule (which terminates at 120,000 miles). I’ve always thought 30,000-40,000 mile transmission services were optimal. There is no dip-stick, which I know is becoming more typical of luxury cars, so I can’t visually assess the condition of the fluid. Visiting some Infiniti forums reveals the transmission is effectively sealed to shade tree mechanics, and requires a visit to the dealership if you’re inclined to have it serviced.

I’d love your insight. I know there is no such thing as transmission fluid that never needs changed. I know any dealership I call will disagree with the literature and recommend it needs changed as frequently as I can afford it(~$350 for a flush and fill at the local dealership). What I don’t know is: When does this fluid really need changed, and why is Infiniti keeping it a secret?

Sajeev answers:

The 7-speed Infiniti angle adds a new twist to one of the quandaries that’s been around since the early days of the Piston Slap series.  My first recollection of these “sealed for life” automatic transmissions was the 1997 Chevy Malibu, and the universal truth hasn’t really changed: change the ATF at regular intervals (being vague for a reason) and make sure to use the correct fluid.

Why be vague? Because while most folks wouldn’t go past 100k-150k on transmission fluid if they knew the benefits–and if they kept a car that long–the actual life of transmission fluid varies by owner. If you carry/tow heavy loads in a minivan that idles in traffic to and from school/work in brutally hot weather, consider a more aggressive ATF replacement schedule.  But if you are one person traveling mostly rural highways in cooler parts of the country, you may never need to change the fluid at all.  (slight exaggeration)

So what’s the right move for you?

The path of least resistance is to visit the dealer and have them do the deed, perhaps every 75k or 100k.  Which isn’t a bad idea, and considering your low mileage…when will you reach 100,000 miles? So don’t sweat it!

Send your queries to Spare no details and ask for a speedy resolution if you’re in a hurry…but be realistic, and use your make/model specific forums instead of TTAC for more timely advice.

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Piston Slap: Crystal Ballin’ With Yo Tranny! Mon, 22 Oct 2012 11:26:50 +0000

TTAC Commentator itsgotvtakyo writes:

Hi Sajeev,

I recently purchased a 1999 Honda Accord LX for my sister. It has 115,000 on the ULEV 4cyl and an automatic transmission. The car is very straight and clean on the inside and out for the year and miles. The seller was a middle aged gentleman who bought the car four years ago for his daughter. The vehicle has obviously been maintained but there’s one glaring issue I have my fingers crossed on… the transmission.

It’s not terrible, but there’s something there. The car upshifts perfectly fine without any slipping or seeking and it also downshifts appropriately when called upon. The only issues occur when shifting the car out of park and when coming to a complete stop. There’s a noticeable (to me) pause and a thunk before the car settles. I noticed this on my test drive and, because the car is so strong in nearly every other aspect, made it the focal point of my negotiation. After pointing it out to the owner he agreed that I was not imagining things and something was out of the ordinary. I’m very well aware of Honda’s transmission issues and, by negotiating a purchase price that’s around $1,800 less than what a comparable 100% no issue car might go for, I’m relatively well protected. An absolute worst case scenario will cost us in inconvenience and time, not dollars. My question is how much life does this tranny realistically have? The current fluid is dirty but not burnt and it will be drained, filled, driven 4X with Honda ATF, along with a couple other piece of mind maintenance items before my sister starts driving it. How much time might that buy me? Is it possible the situation could be resolved completely?

I broke plenty of Hondas before I figured out there’s no way to make big, reliable, forced induction power without spending money, but obviously none of those cars were automatics. In fact, I think a manual transmission is one of the only things that I haven’t broken at some point or another. The Honda forums I used to frequent have been overrun with young kids and idiots for the most part, and the older guys that do know what they’re talking have the same lack of experience with automatic Hondas as I do. The car will get a re-manufactured transmission if it has to but that’s something I’d obviously like to avoid if at all possible. Thanks to you and the commenters for any insight.

Sajeev answers:

Oh boy, another automatic tranny problem. I don’t have a problem repeating myself, but perhaps my best comments on this matter are behind me.

So now I wonder how stupid I sound when Armchair Quarterbacking this play. Because people say some pretty stupid things when analyzing/complaining about a sports team during a big game. Our opinions neither help nor hurt: how many passes have we thrown with a large man barreling down towards us, ready to “profit” from our faceplant?  How do we know what’s going on inside the Accord’s gearbox without tearing it apart? It is the same thing.


BACK ON TOPIC (finally): what would I recommend?  Change the fluid, make sure your sister comes to a complete stop between Reverse/Drive engagement, and hope for the best.  If not, it sounds like you got the Accord for a good price, so find a transmission rebuilder with a good reputation before you need one. That last sentence will save thousands and hours/days of headaches, but adding a coupla cups of sawdust to a failing gearbox isn’t a bad idea too.**

 **Except it is a bad idea. Unless you really, really love sawdust. Which you do not.

Send your queries to Spare no details and ask for a speedy resolution if you’re in a hurry.




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Piston Slap: If you must tow with a Minivan… Mon, 09 Apr 2012 11:50:32 +0000
TTAC Commentator 70Cougar writes:
Dear Sajeev:

My wife has a 2005 Odyssey with 50,000 miles.  To date, we’ve had no problems with the transmission, but I keep reading about how the transmission on the Odyssey isn’t cut out for a vehicle that heavy.  I’ve been contemplating getting a utility trailer for it (although, shockingly, my wife isn’t too hip on having a utility trailer in the driveway) and, in the course of my research, I’ve found that a transmission cooler is recommended if you’re going to haul a trailer. Is it worthwhile to install a transmission cooler even if I don’t get a trailer?  Is there any downside to transmission coolers (e.g., the trans runs cold for too long)?

My wife has a 5 mile commute (10 miles round trip) and we hope to keep the van at least another 5 years.

Sajeev answers:

Before we start, it’s time to change your transmission fluid.  The reason is twofold: transmission fluid has a finite lifespan, and it will die at the mere sight of a utility trailer attached to its minivan home. I love minivans for their efficient use of space and command seating position, but their transaxles are never good enough.

I think every minivan needs the largest external transmission cooler possible behind the front bumper.  That is almost as important as regular fluid changes.  If you plan on towing anything, carrying enough people/cargo to make the rear springs sag, and/or live in a climate that’s brutal on transmission fluid temperatures, both are mandatory. I’d consider annual transmission fluid changes on any minivan that tows on a regular basis, at highway speeds.

A downside to transmission coolers?  Not that I can think of. Because transmission fluid gets far hotter than engine coolant (hence why many tranny coolers are just a heat exchanger inside the engine radiator) the odds of being too cold aren’t a big concern.  But if you aren’t a Houstonian like yours truly, maybe you will need a radiator block-off pad for your front bumper…in the Yukon Territory.

Send your queries to Spare no details and ask for a speedy resolution if you’re in a hurry.
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Piston Slap: LeMons racer seeks Minivan Normalcy Fri, 09 Mar 2012 12:04:57 +0000


Brian writes:


Heeding the call for silly, not-really-that-good letters…plus I wrote you a while back about my Freestyle.  Since then, my wife actually sat in a minivan, and that’s the direction we are heading.  We are looking at replacing it quickly so that she can take the three kiddos to Grandma’s house while I enter Lemons South this March. 

Her peace of mind at Grandma’s house is well worth my ‘not-having-the-phone-ring-contantly’ while at the race, so I agree with her timeline (she doesn’t trust the Freestyle enough to make the trip – she had good ears and hears something bad in the transmission already at 10k on the latest reman unit).  So here is the thing: in 2011, Dodge went to the Pentastar in the minivan.  I am of two minds regarding my decision of a 2008, 2010 or a 2011 (Karesh will love the fact that Truedelta eliminated 2009′s for me – gotta love actual data!).

Pentastar: New, efficient, clean, powerful, 6 speed auto

3.8/3.3: Well known, service proven, 4 speed auto

At first I was reluctant to get a Pentastar, but since it’s going to be the only V6 Chrysler makes, chances are the flaws will be fairly well worked out, and since they started putting it in cars in 2007, it has been along for a while.  The older engine has been around FOREVER, which is pretty nice, although the fuel economy and performance will suffer.  Sounds like the 6 speed transmission is mostly based on the four speed, so I guess I should not be worried about that, but feel free to chime in here as well.

What say you?

Sajeev answers:

Wait, you are a LeMons racer? No wonder you actually considered the CVT to 6-speed swap on your old Freestyle! You are nuts!!!

Wait, that’s being real mean: I meant to say that people like you aren’t normal.  I should know, as I listen to your collective bullshit on a regular basis as a LeMons judge in Texas. That said, it’s nice to see that you and your wife have agreed on something far better for your situation.  Minivans rock.

Except they are all under-transmissioned for the loads carried in them. And while Chrysler’s transaxles are legendary for their LeMons-like durability in pure street circumstances, we might not have enough data to verify the new 6-speed’s worthiness in modern Mopar Minivans.  Cue Michael Karesh!

I would buy the new model simply on performance alone.  Modern close ratio 6-speed gearboxes are absolutely wonderful for launching oversized beasts while retaining decent highway cruising. If anything, the new technology will be more durable simply because they move a van more effortlessly, less stressfully.

My advice is always the same for all Minivans, as they all have the same Achilles’ heel: flush the transmission fluid every 1-3 years (depending on mileage and the weight of your cargo) and install the biggest damn transmission cooler you can find.  Run it in series with the factory radiator/coolant system, if applicable.

Do it and you’ll never feel like you’re Freestylin’ ever again.


Send your queries to . Spare no details and ask for a speedy resolution if you’re in a hurry.

]]> 9 Piston Slap: Peace of Mind or Shameless Shill? Mon, 12 Dec 2011 14:46:01 +0000

Eric writes:

I have a 2000 Maxima with about 155k on the clock.  I purchased this car in Los Angeles and since 2005, it’s lived in Ohio and Pennsylvania.  The main issue is that I can tell the transmission is starting to get a bit soft on the 1-2 upshift, specifically once it starts getting cold out.  I presume the primary reason for this is the abuse it’s suffered at my hands.  As it was a California car, it has no traction control and though I love it nine months of the year, it is utterly helpless in the snow—snow tires didn’t seem to help tremendously.  I’ve had to rock myself out a number of times and I presume the trans has gotten overheated at least once.  I’ve been good about changing the fluid (drain and fill 3x, filter too) about once a year but I think I’m near the end on this trans.

So the question is should I seek out a used AT and have it swapped, send out for a quality rebuild or just replace the Max outright?  It’s been quite good to me with only minor repairs such as a cat, MAF and coils.  I can happily say that it’s a car that I’ve enjoyed quite a lot and wouldn’t mind keeping—the 3.0 VQ is still strong despite the miles.  The main complicating factor is that my wife’s car is not yet paid off and I don’t think I’ll be able to take on a 2nd auto loan; we still have about 3 years left on the current loan.

I’ve toyed with the notion of adding an older Miata to the stable for summer fun and occasional project; though affordable enough to buy outright and I wouldn’t mind it as a daily driver, I’m sure that it wouldn’t be much fun in the winter.  If I dump the Maxima, what would you think might be a suitable replacement?

Sajeev Answers:

Keep it, because you can’t afford a second loan. And why would you? This is far from a death sentence to your automotive needs, its just giving an old friend a helping hand when they need it the most.

You mentioned regular fluid changes. Good for you!  There’s a slim chance that adding a transmission additive (some recommend Lucas, I will not go that far) will fix the problem and this will be the end of the story for months…or maybe longer.  If so…perfection!

But if not, buying a remanufactured transmission is your best bet.  The moment someone cracks open your autobox for a visual inspection is the time when your hard earned dollars are wasted, misused. At this age and mileage, and transmission should be rebuilt/replaced, not somewhat disassembled, inspected, and a couple of parts fixed.

Who rebuilds a Nissan transaxle decently?  Not entirely sure. I’ve been bitten by local shops that never knew the specifics of a certain manufacturer’s design, so I tend to err on the cautious side: either get one from Nissan with a factory warranty or ring up the folks at Jasper.  As their website says, the 3 year warranty and quality control procedures gives “Peace of Mind” that isn’t available by a local shop.  And they usually drop ship to your trusty mechanic, for a quick install.  I am usually hesitant to outright recommend a particular vendor, but Jasper seems to give people on many forums just what their website promises, no matter the make and model.

Best and Brightest: approve or disapprove of this particular shameless shill?


Send your queries to . Spare no details and ask for a speedy resolution if you’re in a hurry.

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Piston Slap: Honda Slushbox Fail…Averted! Mon, 24 Oct 2011 19:22:20 +0000
Jonathon writes:

I’ve been remiss about getting results back to readers.  I took the car to the Honda dealer who pushed hard for the power flush . . . only to have the technician do the 3X manual flush.  Turns out that only some 2003 V6 Accords have the available connections to handle power flushing.

Results?  The transmission has been Smoooooooooth ever since — how could it NOT be when the old fluid looked and smelled like old, overcooked coffee? Because the final draining still smelled a little off, I’ll probably do yet another tranny drain with the next oil change.

 Thanks for the advice.

Sajeev Answers:

Who-hoo! I take any victory I can get in the Piston Slap business.  Excuse me while I shamelessly pat myself on the back. Par-taaaay time, son!!!

Okay, serious time.  This letter is proof that regular fluid changes ensure a healthy and happy transmission or transaxle.  Combined with common sense actions (like coming to a stop between reverse and drive engagement) and a large aftermarket transmission cooler for those who must endure hot summers in urban traffic. Or for anyone who loads up their whips more than with just yourself, your iPod and a latte.

Best and Brightest, will you accept a challenge to do just this for your personal slushbox?

Send your queries to . Spare no details and ask for a speedy resolution if you’re in a hurry.

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Piston Slap: Dreading “The Dreaded” ATF Flush? Wed, 03 Aug 2011 15:04:54 +0000

Jackson writes:

I own a 2001 Nissan Maxima and a 2006 Corvette, both purchased new w/cash. I know the Maxima with 105,000+ miles has had two ATF services, which included the “dreaded ATF Flush”. So far the thing keeps running, only issue (unrelated) was a Cat replacement (99,000) and 3 O2 sensors around the same time.

The 2006 Corvette at 5 years and 42,600 miles is due for a coolant service and I see that the ATF service is 50,000 (harsh) or 100,000 (normal). So far expenses have been limited to gas, once a year oil changes and a set of tires at 26,000 due to some aggressive driving, aggressive factory camber settings and a shard of metal. It’s been spotless so far besides a squeaky roof panel which has been solved by periodic application of Super Lube to some contact points. Should I do an ATF flush for the vette? It would be a BG machine. It’s a warm weather commuter for me (42 miles round trip per day of which 26 is highway miles on which avg. speed 75 mph which is just 3 days a week).

I have taken it on 6 long trips over the years as well as weekend cruises. I do use the paddles about 30% of the time, but do not really hoon it so much the past 2 years after getting 3 speeding tickets in 6 month period…which I fought and is another subject. So please advise.

Sajeev answers:

The easier of the two to E-diagnose is the ‘vette. First, I really hope you ditch(ed) those run flat tires for some donuts befitting a Porsche 911, as that is what the Corvette deserved from the factory. And like much like Motor Trend’s game changing car of the year, the 1997 Chevy Malibu, the C6 Corvette comes with a sealed-for-life transmission. Which begs the question, where did you hear about a 50,000 mile service interval under any condition? Not that owner’s manuals are always right, but I seriously doubt you read that from your glovebox.

These gearboxes normally go 100,000-ish miles before servicing, and your driving habits are definitely within that realm. If you have the motivation, check the fluid’s condition using the link’s info. Odds are the ATF is fine, it should have a pink color with a slightly sweet smell. If it has black-ish bits and smells like a BBQ pit, change it according to factory procedures…and good luck with that!

Now about the Maxima: I question if an “ATF flush” is really something to dread. I’d be quite thrilled with your vehicle, if I were to buy it from you. The biggest plus in the flush’s favor is how it blows out all the old fluid from the torque convertor, which is essentially impossible in vehicles without a drain plug on said convertor’s case. While it doesn’t change the transmission filter, I’ve been told by several techs that this filter isn’t exactly that high tolerance in its filtering capability. Which implies…

…that doing the “dreaded ATF flush” when your fluid degrades essentially makes the transmission filter a lifetime service part. My thoughts are completely debunked over here, but I see their opinion as more applicable to car with more advanced transmission failures.

What say you, Best and Brightest?

Send your queries to Spare no details and ask for a speedy resolution if you’re in a hurry.

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